If the universe is expanding, what is it expanding into ?

Question

what's on the other side ?

Answer 1

This is a very good question, and no one really knows. This probably is completley wrong but here is how I look at it. open up microsoft word and draw a circle. This will represent the universe and it's boundary. Now draw a dot in the middle. This is you, the observer in the inside. Now expand the circle by dragging the corner. This is the expanding universe. You, the dot, will see it moving farther away. Now, drag both the dot and circle. You, the observer  will not notice anything because you are expanding at the same rate.

I don't really know if this is anything like an answer but that is kind of how I view it, doesn't really make sense though.

Answer 2

the universe that preceded ours, or at least its remnants before the big bang (yay, our universe is intergalactic cancer... woo for us). or perhaps it is expanding into nothingness. tad bit hard for us to know with it expanding at the speed of light and all. and what is on the other side. presumably the remnants of the last universe which has become so thin through its own expansion that it is almost all vacuum (with its own laws of physics, presumably differing from our own)

edit:

i probably should also say that we have no absolute theory of what is out beyond our universe. but whether the universe started in the big bang or in some other beginning has no impact on this question as it is expanding, why is not relevent.

Answer 3

Spacetime is highly curved at cosmological scales, and as a result the expansion of the universe is inherently general relativistic; it cannot be understood with special relativity alone. The images to the right show two views of the large-scale geometry of the universe according to the ΛCDM cosmological model. Two of the dimensions of space are omitted, leaving one dimension of space and one of time. The narrow circular end of the diagram corresponds to a cosmological time of 700 million years after the big bang; the wide end is a cosmological time of 18 billion years, where one can see the beginning of the accelerating expansion which eventually dominates in this model. The purple grid lines mark off cosmological time at intervals of one billion years from the big bang. The cyan grid lines mark off comoving distance at intervals of one billion light years. Note that the circular curling of the surface is an artifact of the embedding with no physical significance; space does not actually curl around on itself. (A similar effect can be seen in the tubular shape of the pseudosphere.)

The brown line on the diagram is the worldline of the Earth (or, at earlier times, of the matter which condensed to form the Earth). The yellow line is the worldline of the most distant known quasar. The red line is the path of a light beam emitted by the quasar about 13 billion years ago and reaching the Earth in the present day. The orange line shows the present-day distance between the quasar and the Earth, about 28 billion light years.

According to the equivalence principle of general relativity, the rules of special relativity are locally valid in small regions of spacetime that are approximately flat. In particular, light always travels locally at the speed c; in our diagram, this means that light beams always make an angle of 45° with the local grid lines. It does not follow, however, that light travels a distance ct in a time t, as the red worldline illustrates. While it always moves locally at c, its time in transit (about 13 billion years) is not related to the distance traveled in any simple way. In fact the distance traveled is inherently ambiguous because of the changing scale of the universe. Nevertheless we can single out two distances which appear to be physically meaningful: the distance between the Earth and the quasar in the present era, and the distance between them when the light was emitted. The former distance (shown by the orange line) is about 28 billion light years, much larger than ct. The latter distance is about 4 billion light years, much smaller than ct. Note that the light took much longer than 4 billion years to reach us though it was emitted from only 4 billion light years away. In fact we can see from the diagram that the light was moving away from the Earth when it was first emitted, in the sense that the metric distance to the Earth increased with cosmological time for the first few billion years of its travel time. None of this surprising behavior originates from a special property of metric expansion, but simply from local principles of special relativity integrated over a curved surface.

Note that the universe is not expanding into anything; there is simply more space at later times than at earlier times. Furthermore this notion of "more space" is local, not global; we do not know how much space there is in total. The embedding diagram has been arbitrarily cut off a few billion years past the Earth and the quasar, but it could be extended indefinitely, even infinitely, provided we imagine it as curling into a "spiral of constant radius" rather than a circle. Even if the overall spatial extent is infinite we still say that space is expanding, because locally the characteristic distance between objects is increasing

Answer 4

Space is nothing.

Answer 5

That is the question we should pose to our so-called brilliant scientists who to tell you the truth have absolutely " no " idea. Personally speaking, I have never believed in the " Big Bang " expanding Universe concept but instead think our Universe uses the " Steady State " theory. In other words, our Universe has always existed & always will but I must admit I have no idea what lies outside our Universes boundary !

Answer 6

More universe.

Answer 7

well that one is difficult to explain , and the topic of much work in physics in both astronomy as well as particle physics

if were to assume that the Big bang theory is close to true then

what is happening is that it is growing the space itself is expanding out ward kind of like a rubber ball and then other things like planets ect can move into it

i could be wrong about it eh all i know is a undergrad level of

Astronomy and nuclear physics and this is a feild where were are still learning and writing theories about

a nice book that may make it clearer it the first 4 minutes by steven Hawkins

Answer 8

It's not expanding like a border expands, the space in between galaxies is expanding. There are no borders.

Perhaps it's infinite, perhaps it has some spherical geometry.

No-one belives in steady-state theory anymore, but the person above seems to, although he doesn't seem to actually understand the theory himself, since steady state theory did not predict a finite universe but an infinite one.

A finite, static universe is unstable and would long ago have collapsed on itself due to gravity.